1. Field of the Invention
The present invention relates to surgical instruments for the performance of procedures such as laparoscopic surgical procedures, for example, gall bladder removal operations.
2. The Prior Art
During a typical laparoscopic surgical procedure, such as the removal of a gall bladder, four incisions are made in the patient's abdomen at spread apart locations. The incision descends through the abdominal wall comprising the skin, subcutaneous fat layer, the abdominal muscle layer, the fascia, and the peritoneum.
Through one of the incisions, a laparoscopic sheath will be inserted. A typical laparoscopic sheath comprises a tube, made of plastic or metal, which has a valve structure at one end. The purpose of the sheath is to permit the injection of carbon dioxide gas through the sheath and into the abdominal cavity in order to inflate the abdominal walls to provide room in which to perform the laparoscopic surgical procedure. A number of valve flaps are positioned around the inner periphery of the tube. These valve flaps, which extend in radially inwardly from the inner periphery of an upper section of the sheath, also extend downwardly toward the abdominal cavity and overlap one another, to permit the insertion of surgical instruments down through the tube while maintaining a substantial seal around the instrument to minimize leakage of the carbon dioxide gas and maintain the inflation of the abdominal wall.
During a typical gall bladder surgical procedure, a miniaturized (typically flexible) camera tube, e.g. a laparoscopy (e.g. fiber optic) camera is inserted. Other surgical instruments may be inserted through the other incisions. After the organ has been tied off and then severed, the organ is removed through one of the incisions, typically through the incision through which the laparoscopic sheath has been inserted. Typically, the sheath will be removed and a grasping instrument inserted through the incision in order to grasp the severed and tied off organ and pull it through the relatively small, e.g. 10 mm, incision.
However, often the organ may be enlarged beyond normal size and/or may be filled with stones. While the stones in a stone-filled gall bladder can occasionally be reduced by manual crushing prior to removal of the gall bladder, in the cases when such stones cannot be crushed or in the case of an otherwise abnormally large gall bladder or other organ, the incision through which the organ is to be removed must be enlarged to enable removal of the organ. The outermost skin incision is easily lengthened through the use of a scissors or scalpel. However, to lengthen the incision through the abdominal muscles and the final layers of fascia and peritoneum in the abdominal cavity, small surgical scissors must be inserted through the aperture and the incision must be lengthened at those layers in a blind manner.
Such additional procedures, while typically not involving any additional danger to the patient, do involve added time to the length of the surgical procedure and as well increase the size of the incisions, thus increasing the number of stitches or other surgical repair techniques which must be employed, and increasing the area which must undergo healing.
It would be desirable to provide a more effective and more easily accomplished method in which to enlarge such incisions in a manner which will permit such enlargements to be made more quickly and in a more precise and controlled manner.
These and other objects of the invention will become apparent in light of the present specification and drawings and claims.